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41.
Lonicerae japonicae Flos, a traditional Chinese medicine, has the function of evacuating heat and detoxifying. To promote the optimization of Lonicerae japonicae Flos germplasms and improve the quality of medicinal materials, 55 batches of five Lonicerae japonicae Flos germplasms with the same origin were collected during different periods, a UHPLC-TOF-MS method was established, and 22 kinds of phenolic acids were found and qualitatively analysed. Seventeen phenolic acids were selected for quantitative analysis by UHPLC-QqQ-MS/MS, and the quantitative results were analysed by principal component analysis, orthogonal partial least squares-discriminant analysis, and partial least squares discriminant analysis. The contents of phenolic acids in periods S1–S6 were found to be significantly different. There were also significant differences in the accumulation of phenolic acids in Lonicerae japonicae Flos during different growth periods. Ferulic acid, 5-O-caffeoylquinic acid, and caffeic acid were determined to be important components to distinguish the different growth periods of Lonicerae japonicae Flos. There were significant differences in the phenolic acid content of different germplasms of Lonicerae japonicae Flos, and the total amount of 17 phenolic acids and total acids (chlorogenic acid, 3,5-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid) in “Hua Jin No. 6” was highest, so the quality of “Hua Jin No. 6” was better than that of the four other germplasms. In addition, chlorogenic acid methyl ester and caffeic acid were the smallest markers in combination to distinguish the five germplasms of Lonicerae japonicae Flos.  相似文献   
42.
Present studies have shown that Flos Chrysanthemi has anti-inflammatory and other effects and regulates intestinal function, while the chrysanthemum stem and leaf as non-medicinal parts of chrysanthemum have similar chemical components with chrysanthemum, but the activity and mechanisms are rarely elucidated. Therefore, this study used a DSS-induced zebrafish inflammatory bowel disease model to study the anti-inflammatory and antioxidant effects of chrysanthemum stem and leaf extracts. The results indicate that DSS induction leads to increased secretion of acidic mucin in the intestines of juvenile fish, enlargement of the intestinal lumen and the emergence of intestinal inflammation. Compared with the model group, each administration group differentially inhibited the expression of IL-1β, IL-8 and MMP9 in DSS-induced zebrafish, while upregulating the activity of superoxide dismutase. The quantitative analysis results showed that the flavonoids (including Linarin, Diosmetin-7-glucoside, Tilianin, etc.) and phenolic acids (including Isochlorogenic acid C, Isochlorogenic acid A, 1,3-Dicaffeoylquinic acid, etc.) in the alcohol extract were closely related with both anti-inflammatory and antioxidant activity, while the polysaccharides were also shown a certain anti-inflammatory and antioxidant activity. In conclusion, this study suggests that the flavonoids, phenolic acids and polysaccharides from chrysanthemum stem and leaf extracts can improve inflammatory bowel disease of zebrafish by regulating the expressions of IL-1β, IL-8 and MMP9.  相似文献   
43.
以中药材黄蜀葵花为分析对象,采用高效液相-电喷雾/四极杆-飞行时间串联质谱,识别中药中黄酮醇类化合物.通过解析紫外光谱和二级质谱,识别了17个黄酮醇糖苷和2个黄酮醇苷元,用对照品对照及分析酸水解液的方法进行了验证;并探讨了黄酮醇类化合物的电喷雾/串联质谱(ESI/MS/MS)的裂解方式;在此分析基础上,研究了HPLC指纹图谱和多指标含量测定方法,方法学考察结果表明符合测定要求;采用金丝桃苷、杨梅素和槲皮素作参照,以折算分子量的方法计算相对含量,扩展中药质量控制多指标化的范畴.  相似文献   
44.
A rapid dynamic microwave-assisted extraction and on-line detection by spectrophotometry is proposed for the determination of safflower yellow in Flos Carthami. A high pressure and a peristaltic pump were used to deliver the solvent. A TM010 microwave resonance cavity was applied to concentrate the microwave energy and the forward power about 60 W was enough for the extraction. Other extraction conditions also were examined and optimized. In this work, the extraction process can be monitored by measuring the absorption of safflower yellow in the extract, which would be convenient for rapid optimization of the extraction process. The detection and quantification limits are 8 and 27 μg mL−1, respectively. The within-day and between-day precision (R.S.D.) are 1.6-3.2% and 2.8-4.2%, respectively. Compared with off-line detection, the proposed method may provide more rapid measurement and is more convenient for obtaining continuous measurements.  相似文献   
45.
A fast high-performance liquid chromatography (HPLC) method with diode-array detection (DAD) and time-of-flight mass spectrometry (TOF/MS) has been developed for the analysis of multi-constituent in Yinhuang granules, a well-known combined herbal remedy prepared from the extract mixtures of Flos Lonicerae and Radix Scutellariae. The fast HPLC analysis was performed on an Agilent ZorBax SB-C(18) column (4.6×50 mm, 1.8 μm) and 0.2% aqueous formic acid and acetonitrile was the optimum mobile phase for gradient elution in 17 min, which is five times faster than the performance of conventional columns packed with 5.0 μm particles. With various fragmentor voltages in TOF/MS, accurate mass measurements (<5 ppm error) for molecular ions and characteristic fragment ions represented reliable identification criteria for different constituents. A total of 28 compounds, including nine phenolic acids, three iridoid glycosides and nine saponins from Flos Lonicerae and seven flavonoids from Radix Scutellariae, were identified or tentatively characterized in the extract of Yinhuang granules. The established fast HPLC-DAD-TOF/MS method turns out to be useful and efficient for quality control of this commonly used Chinese herbal preparation.  相似文献   
46.
王智聪  傅荣杰  吉建国  陈波 《色谱》2019,37(2):201-206
采用高分辨采样二维液相色谱法(HiRes 2D-LC)对金银花中绿原酸和木犀草苷进行准确定量分析。第一维液相色谱采用C18色谱柱,以乙腈和0.4%(v/v)磷酸水溶液为流动相进行梯度洗脱;第二维液相色谱采用SB-Phenyl色谱柱,以乙腈和0.5%(v/v)乙酸水溶液为流动相进行梯度洗脱;二维接口采用五位十通阀,并配置2个多中心切割阀,对绿原酸组分和木犀草苷组分进行多次连续切割。实验结果表明,二维液相色谱分析提高了绿原酸和木犀草苷色谱峰的确认能力,可揭示一维液相色谱分析中共洗脱或隐藏峰的信息;高分辨采样模式实现了一维目标组分的片段式整峰切割,提高了二维液相色谱分析的准确定量能力;通过线性关系、基质加标回收和重复性等考察结果,表明高分辨采样二维液相色谱具有优异的定量准确性和重复性,为中药等复杂基质组分样品的分离和准确定量提供了新方法。  相似文献   
47.
高效液相色谱法同时测定金银花中5种有机酸   总被引:8,自引:0,他引:8  
研究了高效液相色谱法同时测定金银花中5种有机酸(咖啡酸,绿原酸,3,5-O-双咖啡酰基奎宁酸,3,4-O-双咖啡酰基奎宁酸,4,5-O-双咖啡酰基奎宁酸)的方法.金银花样品中5种有效成分用体积分数80%甲醇超声振荡提取,选用Waters Symmetry(R) RP18(3.9 mm i.d.×250 mm,5 μm)色谱柱,甲醇和体积分数0.1%的HAc溶液梯度洗脱,流速为0.8 mL/min,用紫外二极管阵列检测器检测.在该色谱条件下,金银花的5种有效成分在30 min内可达到基线分离.方法的加标回收率为97%~101%,相对标准偏差为0.3%~2.4%.本法适合于同时测定各种金银花中5种有机酸.  相似文献   
48.
A simple and accurate reversed-phase high-performance liquid chromatographic (RP-HPLC) method has been developed for simultaneous determination of five flavonoids, spinacetin, quercetin, luteolin, 6-methoxyluteolin, and isorhamnetin, in an extract of the flowers of Inula britannica L., an important Traditional Chinese Medicine (TCM). Samples were extracted with 80% ethanol. Optimum separation and detection were achieved on an ODS-3 column with a methanol–acetonitrile gradient containing 0.49% (v/v) citric acid as mobile phase. The flow rate was 1.0 mL min−1 and detection was at 360 nm. All calibration plots revealed linearity was good (r 2 = 0.999) within the concentration ranges tested. Repeatability was evaluated by performing intra-day and inter-day assays; relative standards deviations (RSD) were less than 2.8%. Recovery of the five flavonoids was between 91.5 and 103.6%, with RSD less than 6.5%. The method was successfully used for analysis of seven samples of Flos Inulae from different parts of China and was found to be simple and efficient.  相似文献   
49.
A method using high-performance capillary electrophoresis with electrochemical detection (CE-ED) has been developed for content comparison of phytoestrogens in both crude and parched Flos sophorae immaturus. Genistin, genistein, rutin, kaempferol and quercetin are important active constituents in this plant. The effects of several factors, such as acidity and concentration of running buffer, separation voltage, applied potential and injection time, were investigated to find the optimum conditions. Detection limits (S/N=3) ranged from 1.1 × 10–7 to 2.8 × 10–7gmL–1 for all five analytes. This method was successfully used to analyse both crude and parched Flos sophorae immaturus after a relatively simple extraction procedure, and the assay results were satisfactory.  相似文献   
50.
Chlorogenic acid and caffeic acid were selected as test samples for separation by the pH‐zone‐refining countercurrent chromatography (CCC). The separation of these test samples was performed with a two‐phase solvent system composed of methyl‐tert‐butyl‐ether/acetonitrile/water at a volume ratio of 4:1:5 v/v/v where trifluoroacetic acid (TFA; 8 mM) was added to the organic stationary phase as a retainer and NH4OH (10 mM) to the aqueous mobile phase as an eluter. Chlorogenic acid was successfully separated from Flaveria bidentis (L.) Kuntze (F. bidentis) and Lonicerae Flos by pH‐zone‐refining CCC, a slightly polar two‐phase solvent system composed of methyl‐tert‐butyl‐ether/acetonitrile/n‐butanol/water at a volume ratio of 4:1:1:5 v/v/v/v was selected where TFA (3 mM) was added to the organic stationary phase as a retainer and NH4OH (3 mM) to the aqueous mobile phase as an eluter. A 16.2 mg amount of chlorogenic acid with the purity of 92% from 1.4 g of F. bidentis, and 134 mg of chlorogenic acid at the purity of 99% from 1.3 g of crude extract of Lonicerae Flos have been obtained. These results suggest that pH‐zone‐refining CCC is suitable for the isolation of the chlorogenic acid from the crude extracts of F. bidentis and Lonicerae Flos.  相似文献   
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